Surgical device

[57] ABSTRACT

A surgical device includes a flexible inner tube having one end dipped in a liquid refrigerant, a flexible outer tube receiving the inner tube and having a freezing tip disposed at a distance from the other end of the inner tube to define a space therebetween, and a vacuum pump for evacuating the outer tube and space, so that the refrigerant is introduced into the space through the inner tube to be evaporated therein to cool the freezing tip.

Claims, 4 Drawing Figures

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PATENTED JAN 141975

3,859,986

SHEET 1 OF 3

FIG. I

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PATENTED JAN 141975 3,859,986

SHEET 2 OF 3

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PATENTED JAN 141975

3,859,986

SHEET 3 OF 3

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3,859,986

SURGICAL DEVICE

BACKGROUND OF THE INVENTION

This invention relates to a surgical device for freezing and treating the diseased portion of the cavity wall such as the inner wall of the stomach.

In surgical operations for cancer of the urinary bladder, hypertrophy of the prostatic gland and the like, there is commonly used a surgical device for freezing the diseased portion to destroy the affected cellular tissue. In the device, the diseased portion is frozen by a freezing metal tip which is cooled in contact with and by evaporation of a liquid refrigerant such as liquid nitrogen. The liquid refrigerant is supplied from a refrigerant container through an inner tube to be evaporated near the metal tip and then the evaporated refrigerant is discharged through an outer tube.

In the conventional device, such a liquid refrigerant is supplied into the first tube by means of pressuring the liquid in the container. Such a means tends to give rise to a complicated construction and difficulties in adjusting the temperature of the metal tip. Further other means to thermally insulate a liquid refrigerant flowing through the inner tube from the outside is unable to satisfy the following requirements. The means has been required to have an excellent insulation and permit the outer tube to be of a small outer diameter.

SUMMARY OF THE INVENTION

It is an object of this invention to provide a surgical device which is simple in construction and provides sufficiently controllable low temperature for freezing the diseased portion.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a sectional view of a surgical device having a surgical instrument and a cystoscope;

FIG. 2 is a side view of a surgical device having the surgical instrument and another cystoscope;

FIG. 3 is a perspective view of an endoscope combined with the surgical instrument; and

FIG. 4 is an enlarged sectional view showing the part of the endoscope illustrated in FIG. 3.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

FIG. 1 shows a surgical device having a surgical instrument 1 and a cystoscope 2 to perform an operation for cancer of the urinary bladder. The surgical instrument 1 includes an elongated flexible outer tube 3 formed of, for example, polytetrafluoroethylene or synthetic resin and a flexible inner tube 4 of a freezingresistant material e.g., fluorine resin which is inserted in the outer tube 3. The outer diameter of the inner tube 4 is made slightly smaller than the inner diameter of the outer tube 3 so as to provide a cylindrical space between the tubes 3 and 4. The outer tube, however, is movably disposed relative to the inner tube. Preferably, the outer tube 3 has a plurality of adiabatic ribs on its inner surface which extend in the lengthwise direction and are equally spaced apart from each other so that the inner tube 4 may be coaxially supported by the outer tube 3. This insures that refrigerant flowing through the inner tube is thermally insulated from the outer tube 3. Alternatively, it is possible to form adiabatic ribs on the outer surface of the inner tube 4.

A freezing metal tip 5 is sealingly mounted on one end of the outer tube 3. A nozzle 6 is formed at one end of the inner tube 4 and slightly spaced apart from the inner surface of the metal tip 5 to define a space therebetween.

A rigid inner sleeve 7 is tightly connected at one end to the other end of the outer tube 3. The inner sleeve 7 is slidably inserted in an outer sleeve 8 which is closed at one end facing the other end of the inner sleeve 7. An O-ring seal 9 is fitted on the outer wall of the inner sleeve 7 so as to enable the inner sleeve 7 to slide through the outer sleeve 8 in an air-tight manner. A threaded hole is formed in the side wall of the outer sleeve 8, preferably near the open end of the outer sleeve 8. A screw 10 is inserted in the threaded hole to fix the inner sleeve 7 to the outer sleeve 8. Since the outer tube 3 is connected to the inner sleeve 7 and the inner tube 4 is fixed to the outer sleeve 8, the distance between the nozzle 6 and the metal tip 5 is easily adjusted by sliding the inner sleeve 7 through the outer sleeve 8. The adjusted distance may be maintained by tightening the screw 10 to fix the inner sleeve 7 to the outer sleeve 8.

An exhaust pipe 11 is connected at one end to the outer sleeve 8 near the closed end and at the other end to a vacuum pump 12. The exhaust pipe 11 has a vacuum gauge 12a so as to measure vacuum pressure in the exhaust pipe 11, outer sleeve 8, inner sleeve 7, and the outer tube 3.

The inner tube 4 inserted in the outer tube 3 extends through sleeves 7 and 8 into refrigerant such as a liquid nitrogen in a refrigerant container 13. To the end of the inner tube 4 dipped in the refrigerant is attached a filter 14 which permits only the refrigerant to pass through the inner tube 4. Part of the inner tube 4 extending from the closed end of the outer sleeve 8 to the container 13 is covered with an adiabatic member 15 of, for example, polystyrene foam.

The surgical instrument 1 may be assembled with the cystoscope 2 wherein the end portion of the outer tube 3 is inserted movably through the sheath 16 of the cystoscope. The freezing tip 5 is extended from one end of the sheath 16. A light guide 17 made of an optical fiber bundle is inserted into the sheath 16 to illuminate the area around the diseased part and freezing tip 5. The sheath 16 is provided with a water inlet 18 and outlet 19 to pass the water through the sheath thereby melting the ice formed on the periphery of the outer tube 3.

The operation of the surgical instrument 1 and cystoscope 2 to treat cancer of the urinary bladder is described below.

First, the diseased portion is located with the naked eye through the sheath while illuminating the inner wall of the urinary bladder. Then, the freezing tip 5 is brought close to the diseased portion. In this condition, the outer sleeve 8 and outer tube 3 are evacuated by operating the vacuum pump 12 so that the refrigerant in the container 13 may be conducted through the inner tube 4 to the nozzle 6 and projected from the nozzle 6 to the freezing tip 5. The refrigerant, when projected from the nozzle 6, is evaporated and discharged through the outer tube 3. The freezing tip 5 is cooled in contact with the refrigerant and also by evaporation of the refrigerant. While observing both the tip 5 and the diseased portion through the cystoscope 2, the tip 5 which is cooled is brought into direct contact with ex

3,859,986 actly the diseased portion to freeze the diseased portion and treat the cancer of the urinary bladder.

Another type of the cystoscope 20 which may be assembled with the surgical instrument 1 will be illustrated with reference to FIG. 2.

The cystoscope 20 includes a sheath 21 with a closed top end, an opening 22 for the surgical instrument and window 23. A telescope 24 is slidably inserted in the sheath through a guide formed in the sheath, which is provided with an ocular 25 at one end and an observing window 26 at its other end. An optical system constructed with lenses and a prism is mounted in the telescope 24 to optically connect the ocular 25 to the observing window 26. The telescope 24 is further provided with a light guide 27 made of a bundle of optical fibers, which guides a light from a light source (not shown) to the windows 23, 26.

The flexible outer tube 3 of the surgical instrument 1 is inserted through the sheath 21 at an opening formed on the base side thereof. The top portion of the outer tube 3 and metal tip 5 are extended from the opening 22 near the window 23. The extended portion of the outer tube 3 may be controlled to vary its inclined angle to the longitudinal axis of the telescope by operating an angle adjusting mechanism 28. The mechanism 28 may be designed to have the same construction as a conventional forceps raising mechanism of an endoscope. The mechanism 28 includes a pivoted arm mounted in the sheath and a wire one end of which is connected to the arm and the other end of which is connected to a lever 29 mounted on the base of the sheath. The arm may be pivoted by the operation of the lever 29 to change the inclined angle of the outer tube 3.

The operation of the surgical device shown in FIG. 2 is substantially similar to that of FIG. 1 and thus omitted in the description.

FIGS. 3 and 4 show a well known endoscope 30 combined with the surgical instrument 1 described above, which includes a control unit 31, a flexible tube 32 to be inserted into the body cavity and a distal end 33 attached to the end of the flexible tube 32. The distal end 33 is provided with a viewing window 34, an illuminating window 35 for illuminating the viewing field of the window 34 and a forceps opening 36, which are formed on the front side of the distal end 33. The viewing window 34 is optically connected to an ocular 37 mounted on the control unit 31 through a bundle of optical fibers arranged in the flexible tube 32. The illuminating window 35 is optically connected to a light source (not shown) through a light guide disposed in the flexible tube 32 and control unit 31. The control unit 31 also includes a forceps inlet opening 39 through which a forceps (not shown) may be inserted into the forceps channel provided in the flexible tube 32 until the end of the forceps extends out through the forceps opening 36 of the distal end 33. In the distal end near the forceps opening 36 there is arranged a forceps raising mechanism 40 which is mechanically connected to the control unit 31 through a wire, so that the raising mechanism 40 is operated by the control unit 31 to change the inclined angle of the extended portion of the forceps. The endoscope 30 is further provided with a bending mechanism (not shown) which is also operated by the control unit to adjustably vary the bending angle of the portion of the flexible tube 32 near the distal end 33.

In operation, the surgical instrument 1 is combined with the endoscope 30, as shown in FIG. 3. The outer tube 3 of the surgical instrument is inserted into the forceps inlet opening 39 of the latter endoscope to extend the top of the outer tube 3 and the metal tip 5 from the forceps opening 36 in the distal end 33, instead of a conventional forceps. The distal end 33 and flexible tube 32 are inserted into the cavity of a human body, together with the outer tube 3 and metal tip 5 of the surgical instrument. Then, the diseased portion is observed through the ocular 37 and viewing window, and the inclined angle of the extended portion of the outer tube 3 is adjusted by operating the forceps raising mechanism to allow the metal tip 5 to contact with the diseased portion. Operation of the surgical instrument is similar to that detailed in connection with FIG. 1 and thus omitted in the description.

With the described surgical devices, the diseased portion of the human body may be frozen by direct contact with the metal tip which has been cooled in the following manner. The liquid refrigerant contained in the container 13 is sucked into the inner tube 4 and then sprayed or projected from the nozzle 6 into the evaporating space between the nozzle 6 and the inner surface of the metal tip 5, by driving the vacuum pump 12 to evacuate said evaporating space through the discharge tube 11 and the outer tube 3. The projected refrigerant may be evaporated in the evaporation space to effectively cool the metal tip, since the evaporating space has large dimensions relative to the opening of the nozzle. The dimensions of the evaporating space may be adjustably changed by moving the inner sleeve 7 through the outer sleeve 8 along its longitudinal axis, so that the temperature of the metal tip may be easily controlled.

The vacuum means such as pump 12 evacuates the cylindrical space between the outer tube 3 and inner tube 4, so that the liquid refrigerant in the container 13 may be introduced into the evaporating space through the inner tube 4, and also the nozzle 6 and the liquid refrigerant flowing through the inner tube may be thermally insulated from the outside.

In the surgical device according to the present invention supplemental means for pressuring the liquid refrigerant may be added to the vacuum means so as to introduce the refrigerant into the evaporating space.